FUNGI IMPERFECTI. 



SPHAEROPSIDIACE.E. 



BOTRYODIPLODIA, SP. 



(Root disease of Coconut.) 



The leaves first show signs of the disease. They 

 become wilted.and yellow at their tips, and finally dry up, 

 blacken and hang down. Shedding of the affected leaves 

 sometimes results ; the leaf base, however, remains 

 attached to the tree. The nuts are shed in all stages, 

 irrespective of size. The stem has a sour smelling, red 

 discolouration which commences at the level of the ground 

 and extends upwards. 



The roots, when examined microscopically, are seen to 

 contain a mycelium composed of dark-coloured, septate 

 hyphae which run between and through the cells. All 

 tissues of the root appear to be attacked. 



The disease occurs in Trinidad and in British Guiana, 

 and appears to have been but little investigated. 

 Recently Mr. Hart has reported a disease of the coconut 

 which he considers to be caused by Diplodia cacaoicola ; 

 whether the two are identical or not cannot be definitely 

 said. 

 STOCKDALE : West Ind. BulL, Vol. IX, p. 363. 



DIPLODIA CACAOICOLA, P. HENN. 

 (Die-back of Cacao and brown rot of Cacao Pods.) 



The fungus was originally described from the Cameroons 

 in the year 1896 ; since then, it has been reported from the 

 West Indies, Surinam, Ceylon, Java, Samoa, and St. 

 Thome (West Africa). It has a wide area of geographical 

 distribution and represents the most serious fungus pest on 

 cacao in the West Indies. 



The fungus attacks both the stem and fruits of the cacao 

 plant. The disease of the stem is known as " die-back," 

 owing to the characteristic dying back of the affected 

 shoots. The younger shoots are usually first affected ; 

 later on, the disease spreads to the older branches and 

 sometimes even to the trunk. Occasionally the diseased 

 area on the trunk may be limited, in which case a canker 



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